Google has expanded its search blacklist to include many of the top file-sharing sites on the Internet, including The Pirate Bay. The changes were quietly processed and appear to be broader than previous additions. Google's blacklist prevents the names of sites appearing in their Instant and Autocomplete search services, while the pages themselves remain indexed.

Since January 2011, Google has been filtering “piracy-related” terms from its ‘Autocomplete‘ and ‘Instant‘ services.

Google users searching for terms like “torrent”, “BitTorrent” and “RapidShare” will notice that no suggestions and search results appear before they type the full word. As a consequence, there’s sharp decrease in Google searches for these terms.

Initially only a handful of “piracy-related” terms were censored, but a recent update to the blacklist includes nearly all the top file-sharing websites.

Searches referring to torrent sites such as “thepiratebay,” “the pirate bay,” “isohunt,” “torrentreactor,” “btjunkie,” “kickasstorrents,” “sumotorrent,” “btmon,” “extratorrent” and many others are now excluded from ‘Autocomplete‘ and ‘Instant‘. Interestingly, the full url “thepiratebay.org” is still offered as a suggestion.

The new list further includes several cyberlocker websites that were perviously left unfiltered, such as “4shared,” “filesonic” and “fileserve.” Although Google doesn’t censor the content of the websites in question, the Google searches for the affected terms drop significantly as can be seen below.

Drop in Hotfile searches after it was censored in January.

By voluntarily censoring parts of their search services, Google is trying to keep on friendly terms with copyright holders. The downside to this is that they put perfectly legitimate companies such as BitTorrent Inc and RapidShare at a disadvantage.

There is currently no clear definition of what Google considers to be piracy-inducing, but Google claims that the blacklist helps to reduce online piracy.

“While there is no silver bullet for infringement online, this measure is one of several that we have implemented to curb copyright infringement online,” Google spokesman Mistique Cano previously told TorrentFreak.

“This is something we looked at and thought we could make some narrow and relatively easy changes to our Autocomplete algorithm that could make a positive difference,” Cano added.

How positive this difference really is, of course depends on who you ask. IsoHunt owner Gary Fung told TorrentFreak that Google is going down a dangerous path.

“It’s a lot more subtle than the censorship attempts made possible by the pending PROTECT IP and SOPA bills, but it’s still censorship and it starts small. Google is increasingly becoming a self-righteous Big Brother of the Web. So much for ‘Do no evil’,” Fung told us.

A Pirate Bay insider also told TorrentFreak that Google doesn’t live up up to its famous motto.

“”It’s just another step towards censoring their search engine altogether – without a legal basis. We’re also wondering why this happens at almost the same time as they’ve released Google Music – a service where they sell music which in some cases might be found on The Pirate Bay,” he added.

Despite criticism from the public and the businesses affected by their blacklist, Google has said that it will continue to expand its piracy filter. The big question is, where will they draw the line?